// will make my data calls like this: https://observablehq.com/@cengique/api-data-example
// and return labeled nodes and edges
// the labels will have to be pre-flattened because enslavers and enslaved will have differently-structured biographical data, and we don't want to deal with that in javascript -- and we should assign enslavers and enslaved different colors on the graph (and maybe subdivide enslavers based on roles -- the problem here being that some have multiple roles, so that makes for a lot of individuated groups)
// we could also pre-calculate the maximum size of the nodes, as we want that non-linear -- some of the buyers are so outsized that they literally block the graph
// and inputs like this: https://observablehq.com/@observablehq/interactivity-in-observable#range
json_data=FileAttachment("graphready@3.json").json();
myChart={
const div = html`<div style='max-width: 900px; overflow-x: auto; padding: 0px; margin: 0px;'></div>`;
const svg = d3.select(div)
.append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform", `translate(${margin.left},${margin.top})`);
//appending little triangles, path object, as arrowhead
//The <defs> element is used to store graphical objects that will be used at a later time
//The <marker> element defines the graphic that is to be used for drawing arrowheads or polymarkers on a given <path>, <line>, <polyline> or <polygon> element.
svg.append('defs').append('marker')
.attr("id",'arrowhead')
.attr('viewBox','-0 -5 10 10') //the bound of the SVG viewport for the current SVG fragment. defines a coordinate system 10 wide and 10 high starting on (0,-5)
.attr('refX',23) // x coordinate for the reference point of the marker. If circle is bigger, this need to be bigger.
.attr('refY',0)
.attr('orient','auto')
.attr('markerWidth',13)
.attr('markerHeight',13)
.attr('xoverflow','visible')
.append('svg:path')
.attr('d', 'M 0,-5 L 10 ,0 L 0,5')
.attr('fill', '#999')
.style('stroke','none');
const dataset=json_data;
console.log(dataset);
// Initialize the links
const link = svg.selectAll(".links")
.data(dataset.links)
.enter()
.append("line")
.attr("class", "links")
.attr('marker-end','url(#arrowhead)') //The marker-end attribute defines the arrowhead or polymarker that will be drawn at the final vertex of the given shape.
//The <title> element provides an accessible, short-text description of any SVG container element or graphics element.
//Text in a <title> element is not rendered as part of the graphic, but browsers usually display it as a tooltip.
link.append("title")
.text(d => d.type);
const edgepaths = svg.selectAll(".edgepath") //make path go along with the link provide position for link labels
.data(dataset.links)
.enter()
.append('path')
.attr('class', 'edgepath')
.attr('fill-opacity', 0)
.attr('stroke-opacity', 0)
.attr('id', function (d, i) {return 'edgepath' + i})
.style("pointer-events", "none");
const edgelabels = svg.selectAll(".edgelabel")
.data(dataset.links)
.enter()
.append('text')
.style("pointer-events", "none")
.attr('class', 'edgelabel')
.attr('id', function (d, i) {return 'edgelabel' + i})
.attr('font-size', 10)
.attr('fill', '#aaa');
edgelabels.append('textPath') //To render text along the shape of a <path>, enclose the text in a <textPath> element that has an href attribute with a reference to the <path> element.
.attr('xlink:href', function (d, i) {return '#edgepath' + i})
.style("text-anchor", "middle")
.style("pointer-events", "none")
.attr("startOffset", "50%")
.text(d => d.type);
// Initialize the nodes
const node = svg.selectAll(".nodes")
.data(dataset.nodes)
.enter()
.append("g")
.attr("class", "nodes")
.call(d3.drag() //sets the event listener for the specified typenames and returns the drag behavior.
.on("start", dragstarted) //start - after a new pointer becomes active (on mousedown or touchstart).
.on("drag", dragged) //drag - after an active pointer moves (on mousemove or touchmove).
//.on("end", dragended) //end - after an active pointer becomes inactive (on mouseup, touchend or touchcancel).
);
node.append("circle")
.attr("r", d=> 17)//+ d.runtime/20 )
.style("stroke", "grey")
.style("stroke-opacity",0.3)
.style("stroke-width", d => d.size/10)
.style("fill", d => colorScale(d.group))
node.append("title")
.text(d => d.id + ": " + d.label + " - " + d.group);
node.append("text")
.attr("dy", 4)
.attr("dx", -15)
.text(d => d.name);
node.append("text")
.attr("dy",12)
.attr("dx", -8)
.text(d=> d.size);
//Listen for tick events to render the nodes as they update in your Canvas or SVG.
simulation
.nodes(dataset.nodes)
.on("tick", ticked);
simulation.force("link")
.links(dataset.links);
// This function is run at each iteration of the force algorithm, updating the nodes position (the nodes data array is directly manipulated).
function ticked() {
link.attr("x1", d => d.source.x)
.attr("y1", d => d.source.y)
.attr("x2", d => d.target.x)
.attr("y2", d => d.target.y);
node.attr("transform", d => `translate(${d.x},${d.y})`);
edgepaths.attr('d', d => 'M ' + d.source.x + ' ' + d.source.y + ' L ' + d.target.x + ' ' + d.target.y);
}
//When the drag gesture starts, the targeted node is fixed to the pointer
//The simulation is temporarily “heated” during interaction by setting the target alpha to a non-zero value.
function dragstarted(d) {
if (!d3.event.active) simulation.alphaTarget(0.3).restart();//sets the current target alpha to the specified number in the range [0,1].
d.fy = d.y; //fx - the node’s fixed x-position. Original is null.
d.fx = d.x; //fy - the node’s fixed y-position. Original is null.
}
//When the drag gesture starts, the targeted node is fixed to the pointer
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
//the targeted node is released when the gesture ends
// function dragended(d) {
// if (!d3.event.active) simulation.alphaTarget(0);
// d.fx = null;
// d.fy = null;
// console.log("dataset after dragged is ...",dataset);
// }
//drawing the legend
const legend_g = svg.selectAll(".legend")
.data(colorScale.domain())
.enter().append("g")
.attr("transform", (d, i) => `translate(${width},${i * 20})`);
legend_g.append("circle")
.attr("cx", 0)
.attr("cy", 0)
.attr("r", 5)
.attr("fill", colorScale);
legend_g.append("text")
.attr("x", 10)
.attr("y", 5)
.text(d => d);
//drawing the second legend
const legend_g2 = svg.append("g")
//.attr("transform", (d, i) => `translate(${width},${i * 20})`);
.attr("transform", `translate(${width}, 120)`);
legend_g2.append("circle")
.attr("r", 5)
.attr("cx", 0)
.attr("cy", 0)
.style("stroke", "grey")
.style("stroke-opacity",0.3)
.style("stroke-width", 15)
.style("fill", "black")
legend_g2.append("text")
.attr("x",15)
.attr("y",0)
.text("more mentions");
legend_g2.append("circle")
.attr("r", 5)
.attr("cx", 0)
.attr("cy", 20)
.style("stroke", "grey")
.style("stroke-opacity",0.3)
.style("stroke-width", 2)
.style("fill", "black")
legend_g2.append("text")
.attr("x",15)
.attr("y",20)
.text("fewer mentions");
return div
};
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